Backpacks are well known in the art and generally comprise a frame upon which fixed straps are placed so that a user can carry the backpack on his or her shoulders. Some backpacks are further provided with a waist strap to solidify the backpack on the person's back. However, one of the problems with these backpacks is that the straps are not longitudinally adjustable. Another problem is that such backpacks are generally not very versatile, since they can only be used in the configuration in which they were designed.
Several examples of backpack frames or adapters exist in prior art including those for use by fire fighters. U.S. Pat. No. 4,685,601 discloses a backpack adapter for carrying fire hoses and associated equipment, such as an air tank. The backpack adapter described therein has a vertical spine and a horizontal cross arm at each end of the spine, spring clips attached to the spine for releasable attachment to an air cylinder and belt fasteners to hold the fire hose unto the backpack, a seat for engaging the bottom of the air cylinder and a handle for manually lifting the backpack.
Similarly, U.S. Pat. No. 4,327,851 discloses a backpack harness assembly where a bottle or a cylinder of gas is to be carried on the back of a user such as a fire fighter. This backpack assembly has a carrier for the cylinder or other load which is hinged in the region of the user's shoulder blades to a back plate. The back plate extends down the back of the user and is hinged at the lumbar region to the frame of a pelvic girdle. According to the specification, such a backpack assembly allows a considerable degree of freedom of movement to the user.
Other types of backpack frames or adapters of more general use include U.S. Pat. No. 3,219,243 which describes a backpack frame which provides both comfort and security to any user because it is presumably immediately adjustable and convertible to custom fit the figures and individual body structure of the user as well as the specific requirements of the material to be carried.
U.S. Pat. No. 4,558,808 discloses a backpack assembly adapted to carry a power chain saw. This backpack assembly presents a shelf life configuration which houses the saw.
U.S. Pat. No. 6,464,118 describes a back supporter load-carrying mechanism. Such mechanism includes a pivotally bonded support element to allow for an even distribution of cargo weight to the lower back of the user, thus eliminating stress to the neck and upper back areas of the user.
However, none of the above inventions and patents, taken either singularly or in combination, is seen to disclose a backpack adapter which is versatile in terms of the different configurations in which it can be used and adjusted as will be subsequently described and claimed in the present invention.